By Len Phillips

The Ivory Silk Tree Lilac is a refined cultivar of the Japanese tree lilac. This tree has a uniform growing habit that is oval, with blue green leaves. This information has been gathered from personal observations of the author, living in Massachusetts, Zone 6, and information provided by J. Frank Schmidt & Son.

Botanical Name: Syringa reticulata 'Ivory Silk'
Trade Name: 'Ivory Silk' Tree Lilac
Parentage: This selection was found by Sheridan Nursery in 1975
Habitat: Species introduced from Japan in 1876
Plant Patent: PP#7205
Height: 20' - 25'
Spread: 15' - 20'
Form: Sturdy, compact, oval growth habit
Bloom Period: Mid June to July bloom,
Flower: Large creamy white clusters 6" - 12" long, begin flowering at an early age, penetrating fragrance like privet, not like common lilac
Fruit: Clusters of capsules turn from green to brown, persistent through winter, capsule is three quarters of an inch long
Summer Foliage: Larger than common lilac, blue green color in summer, 3" - 6" long
Autumn Foliage: Autumn color is sometimes green with reddish band on leaf margin, generally no color, spent flowers are considered unsightly by some
Winter Color: Cherry-like bark plus persistent brown capsules provide winter interest
Bark: Cherry-like, reddish brown that turns heavily lenticelled, gray and scaly with age, glossy, straight trunk
Culture: Full sun is best, flower quantity is greatly diminished in partial shade, pH 6.5 - 8, well drained soil, prefers cool summers
Hardiness Zone: 3 - 8
Growth Rate: Medium, 25' high and 15' wide after 30 years
Pest Problems: Resistant to borer, scale, and mildew, most trouble free lilac
Salt Tolerance: Good tolerance
Planting: Transplants easily by bare root and B&B, well-suited for CU-Structural Soil planting
Pruning: Prune at planting and 3 years later to mature form
Propagation: Not true from seed, must be budded onto Syringa reticulata seedlings or by softwood cuttings
Design Uses: Good street tree for under wires, excellent specimen for residential landscapes as a single tree or in groups
Companions: Use with Phlox subulata ground cover
Other Comments: Medium texture in all seasons, uniform shape, selected by the Society of Municipal Arborists as the 1997 Urban Tree of the Year
Photos and Fact Sheet: J. Frank Schmidt & Son, Co.

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